Garden suite plumbing in Saanich starts with servicing rules. Saanich says you need at least a 3/4 inch (19 mm) water service for the house and the garden suite together, the suite must connect to your existing sanitary service connection with an inspection chamber, and a stormwater connection is required unless you qualify for on-site disposal. A plumber or engineer confirms the service is big enough.
Is my lot eligible for a garden suite in Saanich?
Saanich lists these requirements: an RS or RD zone, a lot in the Sewer Service Area and/or the Urban Containment Boundary, a minimum size of 400 square metres, a minimum width of 12 metres, and a single family dwelling as the principal building. Check your lot on SaanichMap and in the Garden Suite Guide before spending money on plumbing design.
What does Saanich say about the water service?
At minimum you need a 3/4 inch (19 mm) water service for your single family dwelling and garden suite, to meet the BC Building Code and Subdivision Bylaw. Saanich also says you will need to work with a professional plumber or mechanical engineer to determine whether a 3/4 inch service is adequate for the number of fixtures, existing and proposed, on the property.
Its application checklist asks you to know the size of your water service, which you can look up on SaanichMap, and the route your services will take from the municipal connection to the suite. Saanich's pages do not say a second water service is required, so confirm with Saanich Engineering whether a shared service or a separate one fits your lot. We do not recommend guessing: this is the decision that is expensive to change after the trench is open.
How does the suite connect to sewer?
Saanich says your garden suite must connect to the existing sanitary service connection, and your connection must have an inspection chamber installed if one is not currently present. That means the suite's drain line is routed to the existing lateral rather than getting its own connection to the main. If you are unsure who maintains what on a lateral, see who is responsible for the sewer lateral, and consider a camera inspection of the existing line before you add load to it.
And stormwater?
A service connection to the municipal stormwater system, including an inspection chamber, is required unless you meet the criteria for on-site stormwater disposal or another approved system under the Subdivision Bylaw. If you are building a garden suite you are not required to connect the principal dwelling to the storm service.
Which permits apply?
| Permit | From |
|---|---|
| Building permit (each building needs its own) | District of Saanich |
| Plumbing permit | District of Saanich |
| Tree permit, if trees are affected | District of Saanich |
| Gas and electrical permits | Technical Safety BC |
Saanich says a garden suite is built to single family dwelling standards under the BC Building Code and must have its own foundation and drainage system. Home warranty insurance is also required to build a garden suite in BC, and fees for sewer, water and storm connections are set by Saanich's connection fee bylaw. Ask about these early, and see how development cost charges are calculated in Greater Victoria.
What about electrical and gas connections?
Saanich's garden suite guide points to BC Hydro for electrical connection information and to FortisBC if you need to install or move a natural gas line or upgrade a gas service. Each has its own process and timeline, so start those conversations when you plan the trench, not after it is closed. For how servicing, permit fees and size rules add up across the whole project, see this garden suite cost breakdown for Victoria.
What does the rough-in include?
Plumbing for a suite is an ordinary new-construction plumbing package, planned around the service rules above: supply, drain, waste and vent, fixtures, a hot water source and possibly gas. Decisions to settle before framing:
- Hot water. A separate tank or tankless unit for the suite, or an extension of the main house system. See tank, tankless and heat pump water heaters.
- Shutoffs. Separate isolation valves so the suite can be shut off without the house.
- Gas. If the suite has a gas range or heater, it needs a gas permit through Technical Safety BC; see gas permits and the gas fitting pillar.
- Backflow. Some features, such as irrigation, trigger CRD cross-connection rules; see backflow testing.
How do we work on a suite?
We plan the plumbing so the rough-in can be inspected cleanly and the services are sized before the trench is dug. See our new construction service and contact us with your plans.
Frequently asked questions
What size water service does a garden suite need in Saanich?
Saanich says at minimum a 3/4 inch (19 mm) water service for the single family dwelling and the garden suite, and a plumber or mechanical engineer should confirm it is adequate for the fixtures on the property.
Does the suite get its own sewer connection?
Saanich says it must connect to the existing sanitary service connection, which needs an inspection chamber if one is not already there.
Do I need a plumbing permit for a garden suite in Saanich?
Yes. Saanich lists a building permit and a plumbing permit, plus a tree permit if trees are affected. Gas and electrical permits come from Technical Safety BC.
Does the main house have to connect to storm service?
No. If you are applying for a garden suite building permit, Saanich says you are not required to connect the principal dwelling to the storm service.
Where do I check my existing service size?
Saanich points to SaanichMap for service locations and water service size, and to Saanich Engineering for help.
Sources
Last verified October 8, 2026. Rebates, codes and prices change; confirm with the program or Technical Safety BC before you rely on them.